Oil burner



Feb. 22, 1938. c E sw ow 2,108,872

OIL BURNER Filed Jan. 13, 1956 Fig.1.

\nvenTor.

Chufles E. Swallow Patented Feb. 22,1938

UNITED. STATES PATENT OFFICE- ommmm Charles 3. Swallow. m, Mass.Application January 1:, 1m, Serial No. 5am

' (flaims. (c1. isa-m This invention relates to oil burners andparticularly to an oil burner designed for industrial lowtemperaturework.

My invention is embodied in an oil burner of the type having a rotarynozzle, and one object of the invention is to provide an oil burner ofthis type which is highly efllcient and in which the oil will'bethoroughly atomized and mixed with the air to provide the combustiblemixture.

In many burners having revolving nozzles a considerable vacuum iscreated at the end of the nozzle when the burner is in operation, andthe presence of such vacuum tends to retard the flame and also tends tocounteract the atomization of the oil and to cause more or'less oil togather in drops at the delivery end of the nozzle. Another object of myinvention is to provide improvements nozzle situated axially of the airoutlet and forming with the nozzle portion an annular passage for thedischarge of air. The rotary nozzle is provided with a portion ofprogressively-decreasing diameter extending through and beyond thenozzle portion of the housing and which gives the nozzle a streamlineeflect that prevents the rormation of a vacuum at the end of the rotaryelement. This rotary nozzle is rotated rapidly by the air passingthrough the housing from the inlet to the outlet and the parts are soconstructed that the air delivered from the circular air deliveryopening will be given a whirling movement in one direction, while theoil is delivered outwardly into the whirling air current with a whirlingmotion which is opposite to that of the air. The impact of the whirlingoil jets with the oppositely-whirling air results in a line atomizationof the oil and complete mixture of the oil with the air, thus producinga highly semcient combustible mixture.

In order to give an understanding of the invention I have illustrated inthe drawing a selected embodiment thereof which will now be describedafter which the novel features will be pointed out in the appendedclaims.

In the drawing:

Fig. 1 is a sectional view of a burner embodying my invention.

taken through the vanes 23.

Fig. 3 is a fragmentary edge view of the rotor portion of the nomle; and

Fig. 4 is a atic view illustrating the manner in which the oil and airare mixed to produce the combustible mixture. 5

My improved burner comprises a housing member I having an air inletopening 2 and a nozzle portion 3 provided with an air discharge opening4. The nozzle portion 3 is shown as formed in aseparate piece from thebody of the housing I 10 and it is detachably secured thereto throughsuitable bolts 5. The rotary nozzle member is indicated generally at 6and it is provided with a body portion 1 which is rotatively mounted ona tubular extension 8 integral with the body of the 16 housing andprojecting into the nozzle portion 3. Suitable ball bearings 9 areprovided for rotatively supporting the nozzle member 6, there being twoseparate ball bearings which are spaced by the sleeve III that issecured to the tubular 20,

extension 8 by means of a set screw II. The inner end of the body 1extends beyond the inner bearing 9 and a retaining ring I2 issecured'within the inner end of the body I by means or set screws l3.This retainer ring l2 prevents outward 25 longitudinal movement of thenozzle member.

The nozzle member 6 has a portion M of progressively-decreasing diameterextending through and beyond the air discharge opening 4, the projectingend portion l5 of the nozzle being closed 30 and preferably beingrounded as shown. The nozzle is formed with an interior oil chamber itinto which oil is fed through a port Il extending axially of the tubularextension 8, the supply oi. oil from the oil inlet ll being controlledby the 5 usual needle valve l9.

The oil chamber it of the nozzle communicates through openings 20 withan annular chamber 2| having an annular discharge opening or port 22which is situated just beyond the end of the nozzle portion 3 of thehousing. A

Provision is made for rapidly rotating the nozzle during the operationof the burner, for which purpose said nozzle is provided with aplurality of vanes 23 which are acted on by the air traveling throughthe chamber 244st the housing from the inlet 2 to the discharge opening4.

The air delivered to the inlet 2 may be under relatively low pressure,but as the air passes through the vanes 23 it gives the nozzle a rapidrotation so that the oil delivered from the annular discharge opening 22will be thrown outwardly with a rapid whirling motion. The means forrotating the nomle also results in giving the annular stream of air,which is delivered through the annular discharge opening I, a whirlingmotion in the opposite direction to that of the oil, the result beingthat the annular stream of oil which is whirling in one direction isthrown outwardly into an annular stream of air which is whirling in theopposite direction. The result of this is that the oil becomes verythoroughly atomized and mixed with the air, thus producing an extremelyefllcient combustible mixture.

This opposite whirling motion of the air and the ofl results from thecharacter of the vanes 23. The vanes are so constructed that-the twoadjacent faces 25, of any two adjacent vanes are parallel with eachother, as shown in Hg. 2, and are inclined relatively to the axis, asshown in Fig. 3. Because of this parallel arrangement the space 21between any two adjacent vanes 23 has the same width at the periphery ofthe vanes as at the base thereof so that as the moving cur-- rent of airstrikes the faces II of the vanes. as shown by the arrows a in Pig. 3,there is no tendency for the air to flow off from the ends of the vanesbut the full velilect of the air pressure is transmitted to the vanes togive a rotary motion to the nozzle in the direction of the arrows c. Asthe air passesout from the spaces 21 it is given a whirling motion inthe direction of the arrows b and this whirling motion is in an oppositedirection to that in which the nomle is rotating. By this means thespray ofoii will be delivered outwardly from the annular space 22 intothe annular sheet of air which is issuing from the air delivery opening4 with'a whirling motion in a direction opposite to that of the streamof air. This is shown diagrammatically in Fig. t which may be consideredas a view looking toward the nozzle from the right. In said Fig. 4 thecircular row of arrows b indicates the direction of whirling motion ofthe air issuing from the annular port I, and the arrows 11 indicate thewhirling motion of the oil issuing from the annular discharge opening22. Because of the rotative movement of the nozzle the oil is thrownoutwardly in approximately a tangential direction and will thus bedirected against the oppositely-whirling sheet of air illustrated by thearrows b in mg. 4.

The progressively-tapered shape of the portion 6 of the nozzle togetherwith the fact that it projects beyond the nozzle portion I of thehousing gives to the nozzle a streamline effect which permits the airand oil mixture to flow off from the end of the nozzle without creatingany vacuum at said end, the presence of which has a detrimental effecton the operation of the-burner. I claim:

1. An oil burner comprising a housing having an air inlet and a nozzleportion provided with.

a discharge opening, a rotary nozzle member situated axially of saiddischarge opening and forming with the wall thereof an annular airdelivery passage, said nozzle member having an interior chamber and aclosed end projecting beyond the nomle portion of the housing, vanesextending radially from the nozzle member and having inclined faceswhereby the impact of the airpassingthro'ughthe houslngagainstthe vanescauses the nozzle member to rotate and produces a whirling motion in theair passing through the annular air delivery passage, and means fordelivering oil to said interior chamber, said nozzle member beingprovided with an annular oil chamber open at one end on the exteriorthereof at a point Just beyond the nozzle portion of the housing, saidnozzle member also being provided with communicating passages betweensaid annular chamber and the interior chamber. 2. An oil burnercomprising a housing having an air inlet and a nozzle portion providedwith a discharge opening, a rotary nozzle member situated axially ofsaid discharge opening and forming with the wall thereof an annular airdelivery passage, said nozzle member having an interior chamber and aclosed end projecting beyond the nozzle portion of the housing, vanesextending radially from the nozzle member with the adjacent faces of anytwo adjacent vanes parallel to each other and inclined to the directionof air flow, whereby the impact of the air passing through the housingagainst the vanes causes the nozzle to rotate and produces a whirlingmotion in the air passing through the annular air delivery passage, andmeans to deliver oil to said interior chamber, said nozzle member havingan annular oil chamber opening at one end on the exterior thereof andalso having communicating passages between said annular chamber and theinterior chamber, the rotary motion of the nozzle member delivering theoil fromthe open end of the annular oil chamber outwardly into thewhirling'stream of air and with a whirling motion opposite to that ofthe stream ofair. r

3. An oil burner comprising a housing having an air inlet and a nozzleportion provided with a discharge opening, a rotary nozzle membersituated axially of said discharge opening and forming with the wallthereof an annular air delivery passage, said nozzle member having aninterior chamber and a closed outer end which projects through andbeyond the nozzle portion of the housing, the portion of the nozzlemember which thus projects through and beyond the housing having aprogressively decreasing diameter in a; direction toward said closedend, vanes extending radially from the nozzle member and having inclinedfaces whereby the impact of the air passing through the housing I nozzlemember delivering the oil from said annular discharge port outwardlyinto the whirling stream,- of air and with a whirling motion opposite tothat of the stream of air.

CHARLES E. SWALLOW.

